Re: rust in the new tank
Get some course sand and pour in a cup or a little more then shake the heck out of the tank.
Small ball bearings, bee-bees will also work.
There are chemical treatments but if you're talking about the normal surface rust often seen, especially in chrome plated tanks, the sand, bearings, small pee gravel or bee-bees will clean it up for you. Rinse well with hot water afterwards and allow to dry. I light spray of WD-40 will help prevet flash rust until you're ready to add fuel.
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